Field of the Invention
The present disclosure relates to an image processing apparatus and an image processing method.
Description of the Related Art
One focus detection method for an image pickup apparatus is an image pickup plane phase difference method in which focus detection in a phase difference method is performed by a focus detection pixel formed on an image pickup element.
In U.S. Pat. No. 4,410,804, there is disclosed an image pickup apparatus using a two-dimensional image pickup element in which one microlens and a plurality of photoelectric converters obtained by a division are formed for one pixel. The photoelectric converters obtained by the division are configured to receive light from different regions of the exit pupil of the photographing lens via one microlens to divide the pupil. Respective parallax signals obtained by receiving the light by the photoelectric converters obtained by the division may be used to obtain an image shift amount, thereby being capable of performing focus detection in a phase difference method. In Japanese Patent Application Laid-Open No. 2001-083407, there is disclosed adding parallax signals, which are obtained by receiving light by photoelectric converters obtained by a division, to thereby generate a captured image signal.
A plurality of photographed parallax signals are equivalent to Light Field (LF) data, which is information on a space distribution and an angle distribution of light intensities. In Ren Ng, et. Al., “Light Field Photography with a Hand-held. Plenoptic Camera”, Stanford Tech Report CTSR 2005-02, pp. 1-11 (2005), there is disclosed a refocusing technology technique in which a synthetic image at a virtual imaging plane, which is different from an image pickup plane, is rendered by using acquired LF data to change a focus position of the captured image after photographing.
Meanwhile, there is an image pickup apparatus having a function called time-lapse photography (interval photography) for observing a change with time of an object. In the time-lapse photography, an operator specifies photography interval, and every time the photography interval elapses, the image pickup apparatus photographs and records a picture. In Japanese Patent Application Laid-Open No. 2013-062740, there is disclosed a time-lapse photography technique in which, every time the time-lapse photography is performed, an acquired image is output as an image file, and a time-lapse moving image (also known as “time-lapse movie”) file containing the acquired image as one frame of a moving image is generated.
However, in the related art, it has been impossible to perform refocus processing on a time-lapse moving image.